Count Common Words With One Occurrence.java

class Solution
{
    public int countWords(String[] words1, String[] words2)
    {
        HashMap<String, Integer> map1 = new HashMap<>();
        HashMap<String, Integer> map2 = new HashMap<>();
		
        for(String word : words1)
            map1.put(word,map1.getOrDefault(word,0)+1);
        for(String word : words2)
            map2.put(word,map2.getOrDefault(word,0)+1);
			
        int count = 0;
        for(String word : words1)
            if(map1.get(word) == 1 && map2.getOrDefault(word,0) == 1)
                count++;
        return count;
    }
}